铁路站场跨线桥耐候钢箱梁设计与施工

为得到铁路站场跨线桥合理结构并降低全寿命周期成本,结合跨银川车站既有桥梁加宽改建工程,综合各方面因素分析了该工程的主要边界条件,按照德国规范EN03(2007)《Design of Footbridges Guideline》进行人致振动时程舒适度分析。结果表明:大跨度钢结构人行专用桥刚度小,自振频率很难满足国内现行规范要求,须结合国外规范进行人致振动舒适性分析;在桥址环境允许的情况下可采用免涂装耐候钢材;跨线桥多点同步步履式顶推施工要充分考虑施工条件,为避免失稳应综合分析板件的局部受力情况,加强高位落梁的线形和安全性控制。本桥已于2018年底顺利完成全桥施工,为我国首个采用免涂装耐候钢的跨铁路线桥梁。

Design and Construction of Weathering Steel Box Girder of Overpass Bridge in Railway Station Yard

In order to obtain the reasonable structure of overpass bridge in railway station yard and reduce the life cycle cost,the main boundary conditions of the project combining with the widening and reconstruction project of the existing bridge across Yinchuan Station were analyzed in this paper,and the human induced vibration time history comfort was analyzed according to the German standard EN03(2007)《Design of Footbridges Guideline》.The results show that the stiffness of the long span steel structure pedestrian bridge is small,and the natural vibration frequency is difficult to meet the requirements of the current domestic codes,so the human induced vibration comfort analysis should be carried out in combination with foreign codes.The uncoated weathering steel can be used if the environment of the bridge site allows.The construction conditions should be fully considered for the multi-point simultaneous incremental launching construction of overpass bridges.In order to avoid instability,the local stress of slab should be comprehensively analyzed,and the linear and safety control of high-level falling beam should be strengthened.The whole bridge construction has been successfully completed by the end of 2018,which is the first bridge over railway in China to adopt uncoated weathering steels.